GOALS SET FOR THE CURRENT YEAR: 1. To continue the effort in analysis of CMV DNA by various restriction endonucleases. 2. To continue the study of genetic variability of human cytomegalovirus both in vitro and in vivo. 3. To continue the effort in establishment of the genetic relatedness between CMV and other herpes group viruses. 4. To study the mode of CMV transmission and the effect of CMV infection on embryonic development. 5. To continue the effort in location of viral genome, viral antigen and susceptible cell type by nucleic acid hybridization and various immunological techniques. 6. To continue the comparative study of herpes group virus-induced DNA polymerases. The project's overall objectives are (a) to study the molecular biology of human cytomegalovirus (CMV), (b) to elucidate the mode of viral transmission in interuterine infection and (c) to understand the biopathology of CMV infection.